Process of producing caustic soda and barium sulfate.



No. rem 4s.

UNITED STATES l 'axtentedv Septemberi, 1903,

PATENT OFFICE.

CHARLES JACOBS, OF EAST ORANGE, NEW JERSEY, ASSIGNOR, BY MESNEASSIGNMENTS, TO THE UNITED BARIUM COMPANY, OF JERSEY CITY, NEV JERSEY, ACORPORATION OF NEW JERSEY.

PROCESS OF PRODUCING CAUSTlC SODA AND BARIUM SULFATE.

SPECIFICATION forming part of Letters Patent No. 737,740, datedSeptember 1, 1903.

Application filed March 2, 1901. Serial No. 49,641. (No specimens.)

T aZZ whom, it may concern.-

Be it known that I, CHARLES B. JACOBS, a citizen of the United States,residing at East Orange, in the county of Essex and State of 5 NewJersey, have invented certain new and useful Improvements in Processesof Manudrate to form by double decomposition ba rium sulfate and sodiumhydrate; but with this reaction as a basis I may associate otherpreliminary and subsequent reactions to produce other products. Thus toproduce the sodium sulfate for this reaction I may start with sodiumchlorid, decomposing the same with sulfur dioxid, steam, and oxygen andproducing sodium sulfate and hydrochloric acid, and to produce thebarium hydrate required for the reaction I may, according to my PatentNo. 624,041, dated May 2, 1899, use natural barium sulfate, which,treated with carbon in the electric furnace, gives barium oxid andsulfid and sulfur dioxid. The latter product may be used in theproduction of 0 the sodium sulfate from sodium chlorid, as above stated,and the barium oxid and sulfid may be treated with water to producebarium hydrate. It will be noted that while a form of barium sulfid ishere used as a basis or source of the barium element and while oneresultant product of the final reaction is also barium sulfate thelatter product is in a very different and much more valuable state thanthe original natural sulfate, the precipitated o sulfate being morefinely divided and purer than is possible With the natural article andbeing, in fact, salable commercially as blanc fixe or artificial bariumsulfate at a much higher price than the natural article; but if it bedesired to produce only hydrochloric acid and caustic soda then thebarium sulfate resulting from the main reaction may be used over againfor the production of an additional quantity of barium oxid and sulfurdioxid, so that a limited quantity of barium 5o sulfate may be used forthe preparation of an indefinite quantity of such products.

Considering the process as a means of producing caustic soda and bariumsulfate it is carried out as follows: Solutions of barium hydrate and ofsodium sulfate in molecular equivalent proportions containing,respectively, for example, one hundred and seventy-one pounds of bariumhydrate and one hundred and forty-two pounds of sodium sul- 6o fate aremixed and the following reaction takes place:

The sodium hydrate or caustic soda is fil- 6 tered from the precipitateof barium sulfate and evaporated to dryness and then fused and packedfor use. The barium sulfate is washed free from sodium hydrate with hotwater, and if it is to be sold as blanc fixe or pigment it is eitherpacked in the form of paste for use in card and paper sizing or it isdried for mixing with oil for use as a paint.

The sodium sulfate and barium hydrate for use in this process may be theordinary com- 15 mercial products so named; but I prefer to produce thesame from the cheaper naturallyoccurring common salt and barytes. Thecomplete process so carried out would be as follows: Barium sulfate isheated with carbon in the electric furnace according to my Patent No.624,041, dated May 2, 1899, the reaction being as follows:

As stated in said patent, the second reaction does not in general keeppace with the first,

so that in the final product or residue sulfid is formed as Well as theoxid. By treating go the resulting mass or residue with water, however,a portion of the sulfid is converted into hydrate as follows:

a heated chamber or vessel containing sodium chlorid, water or steam andoxygen also being supplied and the following reaction taking place:

The hydrochloric acid passes 0E and is condensed and absorbed with waterand utilized in the usual manner. The sodium sulfate and the bariumhydrate from the electric-furnace reaction are utilized in the formationof barium sulfate and caustic soda, as above described. It will be seenthat this barium sulfate may be used in the regeneration of new portionsof barium hydrate and sodium sulfate.

Having thus described my invention, the following is what I claim as newtherein and desire to secure by Letters Patent:

hydrate With-the sodium sulfate to produce 30 caustic soda and bariumsulfate.

CHARLES E. JACOBS.

Witnesses: ARTHUR P. KNIGHT, J. GREEN.

